- Hannay Reels, Inc. has designed HGR and GR Series (Form H9454-SG) spring and manual rewind cable reels which are designed specifically for use in explosive atmospheres or under hazardous conditions such as aircraft refueling, chemical plant operations, grain elevators, rescue situations or wherever a build-up of static electricity might cause a spark and subsequent explosion. The five models described handle 60 - 200 ft. of static grounding cable.